Kirk was born in San Francisco to a Filipino mother and an Irish Merchant Marine father. He attended De Anza High School in El Sobrante, California when his family moved to the East Bay where he met Les Claypool from the experimental funk metal band, Primus. As a child and teenager, he had great interest in his brother Rick's extensive guitar collection, Rickenbacker Basses and music records, including bands such as Led Zeppelin, Black Sabbath, Status Quo, The Rolling Stones, UFO, and especially Jimi Hendrix. Hammett is quoted as saying he wanted to be Hendrix. He took up the guitar at the age of fifteen, beginning with a Montgomery Ward catalog special and little more than a shoebox with a four inch speaker for an amplifier. After picking up a 1978 Fender Stratocaster, Hammett attempted to customize his sound with various guitar parts, eventually ending up with a 1974 Gibson Flying V. He even took a job at Burger King for a Marshall amplifier.
In 1980, he formed the thrash metal band Exodus with vocalist Paul Baloff, guitarist Gary Holt, bassist Geoff Andrews, and drummer Tom Hunting. He played on Exodus' 1982 Demo. Exodus was a crucial early player in the Bay Area thrash metal movement. James Hetfield and Lars Ulrich had attended an Exodus gig, and after firing previous lead guitarist Dave Mustaine they then invited Hammett to join Metallica, accepted and flew in to replace Mustaine that same afternoon.
- ESP Black & White Flying V (KH-1)
- ESP Black M-II - Skull & Crossbones (KH-2)
- ESP Black M-II - Ouija (KH-2)
- ESP Black Eclipse - Spider (KH-3)
- ESP M-II - Mummy
- Gibson Les Paul
- Jackson Randy Rhodes Model
- Wavecaster Wavemachine Model Guitar
- ESP KH Custom "Dracula"
- ESP KH Custom "Frankenstein"
- Mesa Boogie Temoverb 2x12 Combo Amp
- Mesa Boogie Triaxis Pre-Amp
- Mesa Boogie Strategy 400 Stereo Power Amp
- Mesa Boogie 4x12 Speaker Cabinets
- Mesa Boogie 2x12 Speaker Cabinets
- Mesa Boogie Dual Rectifier Amp
- Garage Days Re-Revisited (1987)
- ...and Justice for All (1988)
- Metallica (1991)
- Live Shit: Binge & Purge (1993)
- Load (1996)
- Reload (1997)
- Garage, Inc. (1998)
- S&M (1999)
- I Disappear (2000)
- St. Anger (2003)
- Death Magnetic (2008)
- Lulu (2011)
- Hardwired...To Self-Destruct (2016)
- 1982 Demo - 1982